Why do some guys take say they like u but take their time to reply to messages?

for various reasons.. either they are busy working or they are trying to play it cool or they are out playing other girls or or their phone is dead or they left it at their friend's house (so i was told anyway) or they are just not serious.. some people say anything.. maybe you need to be cool for once like.. some guys don't wanna be messaged all day 😂